The invention is in the general field of proteins involved in Alzheimer's disease.
Various genes and gene products involved in the development of Alzheimer's disease have been identified. Neuritic plaques characteristic of the disease are composed of .beta.-amyloid (A.beta.), which are oligopeptides of about 40-43 amino acids in length derived from the .beta.-amyloid precursor protein (.beta.APP). Mutations in the gene encoding .beta.APP are associated with some cases of familial Alzheimer's disease. Other cases of familial Alzheimer's disease have been associated with mutations in two other loci, presenilin-1 and presinilin-2.